This undated image provided by the National Transportation Safety Board shows the burned auxiliary power unit battery from a JAL Boeing 787 that caught fire on Jan. 7 at Boston's Logan International Airport. Federal officials said on Wednesday that they are temporarily grounding Boeing's 787 Dreamliners until the risk of possible battery fires is addressed.

Dreamliner batteries under review

By JOAN LOWY and JOSHUA FREED

THE ASSOCIATED PRESS

January 18, 2013 - 2:00 AM

WASHINGTON — Lithium batteries that can leak corrosive fluid and start fires have emerged as the chief safety concern involving Boeing's 787 Dreamliner, a problem that apparently is far more serious than government or company officials acknowledged less than a week ago.

The Federal Aviation Administration late Wednesday grounded Boeing's newest and most technologically advanced jetliner until the risk of battery fires is resolved. The order applies only to the six Dreamliners operated by United Airlines, the lone U.S. carrier with 787s. Other airlines and aviation authorities in other countries quickly followed suit.

Japan's two largest air carriers voluntarily grounded their 787s on Wednesday ahead of the FAA's order following an emergency landing by one of the planes in Japan. On Thursday, the European Aviation Safety Agency ordered all European carriers to ground the jetliner. The Indian government ordered Air India to ground its fleet of six Boeing 787s, and Ethiopian Airlines grounded its four 787s "for precautionary inspection."

FAA Administrator Michael Huerta unequivocally declared the plane safe at a news conference last week even while they ordered a safety review of the aircraft.

However, as details emerged of two battery failures only 10 days apart, it became apparent that the FAA wouldn't be able to wait for completion of its safety review before taking action. An inspection of the All Nippon Airways 787 that made an emergency landing in western Japan found that electrolytes, a flammable battery fluid, had leaked from the plane's main lithium-ion battery. Investigators found burn marks around the damage. Japan's Kyodo News agency quoted transport ministry investigator Hideyo Kosugi as saying the liquid leaked through the electrical room floor to the outside of the aircraft.

In the first battery incident on Jan. 7 in Boston, it took firefighters 40 minutes to put out a blaze centered in an auxiliary power unit of a Japan Airlines 787.

The two incidents resulted in the release of flammable electrolytes, heat damage and smoke, the FAA confirmed. The release of battery fluid is especially concerning, safety experts said. The fluid is extremely corrosive, which means it can quickly damage electrical wiring and components. The 787 relies far more than any other airliner in operation on electronics to function rather than hydraulic or mechanical systems.

Jim McNerney, Boeing's chairman, president and CEO, said the company is working with the FAA to resolve the situation as quickly as possible. "We are confident the 787 is safe and we stand behind its overall integrity," he said in a statement. "We will be taking every necessary step in the coming days to assure our customers and the traveling public of the 787's safety and to return the airplanes to service."